Blastoidea

plural noun

Blas·​toi·​dea

blaˈstȯidēə

: a class, formerly considered a division of Crinoidea, of extinct Paleozoic short-stemmed or stemless pelmatozoan echinoderms shaped somewhat like a flower bud and having five ambulacral areas with slender appendages along their margins and flattened tubes along their internal surface

blastoidean

(ˈ)⸗¦⸗dēən

adjective or noun

Word History

Etymology

New Latin, from blast- + -oidea

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